CN113319188B

CN113319188B - Horizontal floating punching device and method for U-shaped bent chain plate

Info

Publication number: CN113319188B
Application number: CN202110665510.0A
Authority: CN
Inventors: 汪永明; 唐成涛; 蒋晨; 谈莉斌; 芮艳青; 李偎
Original assignee: Anhui University of Technology AHUT
Current assignee: Dragon Totem Technology Hefei Co ltd
Priority date: 2021-06-16
Filing date: 2021-06-16
Publication date: 2022-04-12
Anticipated expiration: 2041-06-16
Also published as: CN113319188A

Abstract

The invention discloses a horizontal floating punching device and a punching method for a U-shaped bent chain plate, and belongs to the technical field of machining. The punching device comprises an upper die mechanism, a guide mechanism, a punching nail driving mechanism, a die core mechanism and a die holder mechanism. The working principle is as follows: the upper die mechanism moves downwards along with the stroke of the punch press, a workpiece pressing plate of the upper die mechanism presses a U-shaped bent chain plate workpiece, and driving pieces at the left end and the right end push driving sliding blocks to move towards the middle along guide rod sliding rails so as to push upper and lower punching nails fixed on a punching nail fixing plate to punch holes on the workpiece; after punching is completed, the punch press returns, the driving piece gradually disengages from the driving slide block, the punching nail retreats under the action of spring force, and the driving slide block retreats and resets; and the spring ejector pin pushes the workpiece loose, the workpiece is taken out, and the punching device is restored to the original state. The invention can effectively solve the problems of back of the punching nail, unsmooth reset of the driving slide block and the like in the punching process, can be applied to automatic processing of the U-shaped bent chain plate, and improves the punching precision and the working efficiency.

Description

Horizontal floating punching device and method for U-shaped bent chain plate

The technical field is as follows:

the invention belongs to the technical field of machining, and particularly relates to a horizontal floating punching device and a punching method for a U-shaped bent chain plate.

Background art:

the steel pin chain is an important basic transmission part and is formed by serially assembling U-shaped bent chain plates and pin shafts section by section. The opening end of the U-shaped bent chain plate is provided with a pair of coaxial negative tolerance pin holes, the tail end of the U-shaped bent chain plate is provided with a pair of coaxial positive tolerance pin holes, and certain symmetry degree of the two pairs of pin holes is required to be ensured. At present, four-hole processing of the U-shaped bent chain plate is often completed by adopting a single-station punch vertical punching mode, manual feeding, discharging and scrap removal are required for the punching mode, the automation of the U-shaped bent chain plate punching processing is seriously influenced, and great potential safety hazards exist. The horizontal floating punching device and the punching method for the U-shaped bent chain plate, provided by the invention, can effectively ensure the punching precision of four holes of the U-shaped bent chain plate, are easy to discharge scraps, can effectively solve the problem of return and blocking of punching nails during horizontal punching, are convenient to use a manipulator to clamp and feed workpieces, can be applied to automatic punching processing of the U-shaped bent chain plate of a pinned chain, and effectively reduce the labor intensity of workers.

The invention content is as follows:

the invention provides a horizontal floating punching device and a punching method for a U-shaped bent chain plate, aiming at the problems in the existing U-shaped bent chain plate punching technology. The horizontal floating punching device comprises an upper die mechanism, a guide mechanism, a punching nail driving mechanism, a die core mechanism and a die holder mechanism.

The upper die mechanism comprises a die handle 1, an upper die holder 2, a workpiece pressing plate 3, an upper die spring guide rod 4, a material pressing spring 5, a hook plate 6, a driving piece 7 and a driving piece fixing plate 8; a flange is arranged at the bottom of the die handle 1, a flange hole is arranged in the middle of the upper die holder 2, and the flange is in clearance fit with the flange hole and is fixedly connected with the flange hole through a bolt; the lower end of the driving piece 7 is provided with a 45-degree inclined plane, the upper end of the driving piece 7 is provided with a tenon, and the tenon of the driving piece 7 is positioned in the mortise of the driving piece fixing plate 8; the driving parts 7 are arranged symmetrically left and right, and the driving parts 7 are fixedly connected to the driving part fixing plate 8 through bolts; the driving piece fixing plate 8 is fixedly connected with the upper die holder 2 through a screw; the detachable hook plate 6 is respectively arranged in L-shaped slotted holes on the front side surface and the rear side surface of the driving piece 7, the hook plate 6 is Z-shaped, and two sides of the hook plate 6 are respectively provided with a protruded cylindrical pin shaft; the workpiece pressing plate 3 is a rectangular plate with two through holes on two sides, the upper die spring guide rod 4 is divided into two parts, the upper die spring guide rod 4 is a long inner hexagon bolt, the workpiece pressing plate 3 and the material pressing spring 5 are sequentially sleeved on the upper die spring guide rod 4 in an empty mode, and the upper die spring guide rod 4 is fixedly connected with a screw hole in the middle of the driving piece fixing plate 8 through a threaded end of the upper die spring guide rod.

The guide mechanism comprises a guide sleeve 9, a guide pillar 10, a spring 11 and a guide pillar base 12; the two guide mechanisms are arranged in total and are symmetrically distributed behind the punching device in the left-right direction; the guide sleeve 9 is fixed at the lower part of the left side and the right side of the upper die holder 2 through bolts, the guide post 10 is fixed at the left side and the right side of a base 27 in the die holder mechanism through the guide post base 12, the spring 11 and the guide sleeve 9 are sequentially sleeved on the guide post 10 in a hollow manner, and the guide sleeve 9 is in clearance fit with the guide post 10.

The punching nail driving mechanism comprises a driving slide block 13, a punching nail fixing plate 14, a workpiece side surface lower pressing plate 16, a workpiece side surface upper pressing plate 17, a lower punching nail 18, an upper punching nail 19, a lower die spring guide rod 21 and a punching nail return spring 22; the nail punching driving mechanisms are of front-back symmetrical structures, and the nail punching driving mechanisms are divided into two parts and are symmetrically arranged on the left side and the right side of the die core mechanism; a 45-degree inclined plane body 1301 is arranged in the middle of the driving sliding block 13, return grooves 1304 matched with the hook plates 6 are formed in two side faces of the inclined plane body 1301, and the hook plates 6 can slide in the return grooves 1304; two through holes 1302 with the same structure are respectively arranged on two sides of the inclined plane body 1301, the through holes 1302 are used for placing the lower die spring guide rod 21 and the punch pin return spring 22, a spring stop 1305 is arranged on the bottom surface of the driving slide block 13, first wing plates 1303 are respectively arranged on the front side and the rear side of the driving slide block 13, and 8 uniformly distributed mounting holes are respectively arranged on the first wing plates 1303; the first wing plates 1303 are fixedly connected with guide rod sliding blocks 31 in the die holder mechanism respectively, and the driving sliding blocks 13 can horizontally move left and right along guide rod sliding rails 30 in the die holder mechanism; the lower punching pin 18 and the upper punching pin 19 are fixedly connected in an upper sunken hole of the punching pin fixing plate 14 respectively; the punching nail fixing plate 14 is provided with two pin holes and four mounting holes, and the punching nail fixing plate 14 is fixedly connected with the driving sliding block 13 through two positioning pins 15 and four hexagon socket head bolts 20; the lower die spring guide rods 21 are four in number, the lower die spring guide rods 21 are long common bolts, the lower die spring guide rods 21 sequentially penetrate through the workpiece side lower pressing plate 16 or the workpiece side upper pressing plate 17, the punching nail return spring 22, the punching nail fixing plate 14 and the driving slide block 13, and the lower die spring guide rods 21 are locked through flat washers 23 and locking nuts 24; a through hole for the lower punch pin 18 to pass through is formed in the middle of the workpiece side lower pressing plate 16, and counter bores matched with the lower die spring guide rod 21 are symmetrically formed in two sides of the workpiece side lower pressing plate 16; the middle of the workpiece side upper pressure plate 17 is provided with a protruding step surface which has the same shape as the upper and lower step surfaces 2503 in the die core mechanism, the upper end of the protruding step surface is provided with a through hole for the upper punch pin 19 to pass through, and two sides of the workpiece side upper pressure plate 17 are symmetrically provided with counter bores which are matched with the lower die spring guide rod 21 for installation.

The mold core mechanism comprises a mold core 25 and a spring thimble 26; the mold core 25 is of a left-right front-back symmetrical structure, the middle part of the mold core 25 is a prismatic structure 2501 with a square base 2502, and the front side and the back side of the prismatic structure 2501 are respectively provided with a second wing plate 2506; the middle of the prism structure 2501 is a square scrap hole 2508, the left end surface and the right end surface of the prism structure 2501 are respectively provided with an upper step surface and a lower step surface 2503, and the distance between the upper step surface and the lower step surface 2503 on the two sides of the die core 25 is matched with the size of a U-shaped opening of a U-shaped bent chain plate workpiece 32; two sides of the upper step surface 2503 and the lower step surface 2505 are provided with guide positioning surfaces 2505 of the U-shaped bent chain plate workpiece 32; an upper punch hole 2507 and a lower punch hole 2504 are respectively arranged on the upper step surface 2503 and the lower step surface 2503, wherein the upper punch hole 2507 is a three-fifths circular arc-shaped through hole; the sizes of the upper die hole 2507 and the lower die hole 2504 are larger than the sizes of two holes of the processed U-shaped bent chain plate workpiece 32, and the positions and the center distances of the upper die hole 2507 and the lower die hole 2504 are consistent with the positions and the center distances of the two holes of the processed U-shaped bent chain plate workpiece 32; the upper punch hole 2507 and the lower punch hole 2504 respectively form a punch-die of the horizontal floating punching device together with the upper punch pin 19 and the lower punch pin 18; a blind hole for mounting the spring thimble 26 is respectively arranged on the square base 2502 at the outer side of the lower punch hole 2504; the die core 25 front and back both sides be equipped with four mounting holes on the second alar plate 2506 respectively, the die core 25 front and back both sides the second alar plate 2506 respectively with guide bar slider 31 in the die holder mechanism links firmly through the bolt, the die core 25 can along guide bar slide rail 30 in the die holder mechanism is left and right level and is floated, and then realizes that the level floats and punches a hole.

The die holder mechanism comprises a base 27, a lower die holder 28, a slider return spring 29, a guide rod slide rail 30 and a guide rod slider 31; the base 27 is fixedly installed on a working table of a punch press, the lower die holder 28 is fixedly connected to the base 27, a square blanking hole 2802 is formed in the middle of the lower die holder 28, square blanking holes with the same size are also formed in the middles of the base 27 and the working table of the punch press, four rectangular grooves 2801 for accommodating the slider return springs 29 and four spring stoppers 2803 are formed in the lower die holder 28, and the spring stoppers 2803 can limit the range of horizontal floating of the die cores 25 along the guide rod slide rails 30; the front side and the rear side of the lower die holder 28 are respectively fixed with the guide rod slide rails 30, and each guide rod slide rail 30 is respectively provided with five guide rod slide blocks 31 with the same structure; the guide bar slide rail 30 and the guide bar slide block 31 are both heavy-duty.

The invention also provides a punching method of the horizontal floating punching device for the U-shaped bent chain plate, which comprises the following specific steps:

a. first, the robot gripper places the U-turn link plate workpiece 32 on the mold core 25, and as the punch slide moves downward, the workpiece pressing plate 3 contacts the U-turn link plate workpiece 32, forcing the U-turn link plate workpiece 32 to move downward along the guide positioning surface 2505, while the U-turn link plate workpiece 32 contacts and presses down the spring ejector pin 26, and then the inclined surface of the driving member 7 contacts the inclined surface 1301 of the driving slide 13.

b. The punch press slide block continues to move downwards, the driving piece 7 pushes the driving slide block 13 to move towards the middle along with the guide rod slide block 31 along the guide rod slide rail 30, the hook plates 6 on the two sides of the driving piece 7 slide into the return groove 1304 of the driving slide block 13, the slide block return spring 29 and the punching nail return spring 22 are compressed, at the moment, the workpiece pressing plate 3 presses the U-shaped bent chain plate workpiece 32 to the punching position of the mold core 25, and meanwhile, the workpiece side surface lower pressing plate 16 and the workpiece side surface upper pressing plate 17 respectively press the left side surface and the right side surface of the U-shaped bent chain plate workpiece 32.

c. The lower punching nails 18 and the upper punching nails 19 on the two sides of the mold core 25 start to contact the U-shaped bent chain plate workpiece 32 under the pushing of the driving piece 7, if the lower punching nails 18 and the upper punching nails 19 on the two sides of the mold core 25 do not synchronously contact the U-shaped bent chain plate workpiece 32, the punching nails firstly contacting the U-shaped bent chain plate workpiece 32 push the mold core 25 to horizontally float left and right along the guide rod slide rail 30 until the punching nails on the two sides synchronously contact the U-shaped bent chain plate workpiece 32, then the lower punching nails 18 and the upper punching nails 19 on the two sides of the mold core 25 synchronously complete the punching of four holes of the U-shaped bent chain plate workpiece 32 under the pushing of the driving piece 7, and punching scraps fall into the scrap holes 2508 in the middle of the mold core 25 and sequentially pass through the square blanking holes 2802 of the lower mold seat 28, the square blanking holes of the base 27 and the square blanking holes of the working table of the punch press.

d. At the moment, the punch slide block reaches the bottom dead center position of the punch, and the stroke is finished.

e. And when the punch press slide block returns, the driving piece 7 is gradually separated from the driving slide block 13, and the driving slide block 13 horizontally moves outwards under the elastic action of the slide block return spring 29.

f. Meanwhile, the punch pin return spring 22 drives the lower punch pin 18 and the upper punch pin 19 to retreat and return.

g. If the reset is blocked, the hook plates 6 on the two sides of the driving piece 7 are inserted into the return groove 1304 to forcibly withdraw the driving slider 13, so as to protect the mold core 25.

h. The spring ejector pin 26 ejects and loosens the U-shaped bent chain plate workpiece 32 on the mold core 25 under the action of spring force, and then the clamping jaw of the manipulator takes out the U-shaped bent chain plate workpiece 32.

i. And the mould is restored to the initial state and enters the next working cycle.

The invention has the following technical characteristics:

1. the horizontal floating punching device for the U-shaped bent chain plate adopts the low-speed heavy-load guide rod slide rail, ensures the movement precision and the punching precision of the die punching nail by driving the slide block 13 to horizontally and transversely move on the guide rod slide rail 30, and is easy to assemble.

2. Adopt unsteady mold core, promptly the second alar plate of both sides around the mold core respectively with the guide arm slider links firmly through the bolt, the mold core can along the level is floated about the guide arm slide rail, and then realizes that the level floats and punches a hole, can effectively solve both sides and punch a nail and can't realize the difficult problem of punching a hole in step, can effectively guarantee the precision of punching a hole.

3. The upper and lower punching nail positions of the die are respectively provided with a workpiece side lower pressing plate and a workpiece side upper pressing plate, and the two springs are respectively matched, so that the workpiece is conveniently clamped when punching is carried out, and the phenomenon that the workpiece is pulled when the punching nail returns is avoided.

4. The die is provided with a mechanical backspacing mechanism, namely, the L-shaped slotted holes on the front side surface and the rear side surface of the driving piece are respectively provided with a detachable hook plate, the driving slide block is provided with a return slot, the driving slide block can be forced to return when the punching is finished, so that the punching nail backspacing process is ensured not to be blocked, and the die core of the die can be effectively protected.

Description of the drawings:

FIG. 1 is a schematic structural diagram of a horizontal floating punching device according to the present invention;

FIG. 2 is a schematic structural diagram of an upper die mechanism in the horizontal floating punching device of the present invention;

FIG. 3 is a schematic structural diagram of a punching pin driving mechanism in the horizontal floating punching device according to the present invention;

FIG. 4 is a schematic structural diagram of a driving slider in the horizontal floating punching device according to the present invention;

FIG. 5 is a schematic structural diagram of a die core mechanism in the horizontal floating punching device of the invention;

FIG. 6 is a schematic structural diagram of a die holder mechanism in the horizontal floating punching device according to the present invention;

FIG. 7A is a schematic structural view of a U-shaped bent chain plate workpiece before being processed by the horizontal floating punching device according to the present invention;

fig. 7B is a schematic structural view of a U-bend link plate workpiece after being processed by the horizontal floating punching device of the present invention.

In the figure: 1. a die shank; 2. an upper die holder; 3. a workpiece pressing plate; 4. an upper die spring guide rod; 5. a material pressing spring; 6. a hook plate; 7. a drive member; 8. a driving member fixing plate; 9. a guide sleeve; 10. a guide post; 11. a spring; 12. a guide post base; 13. driving the slide block; 1301. an inclined plane body; 1302. a through hole; 1303. a first wing plate; 1304. a return slot; 1305. a spring stop; 14. punching a nail fixing plate; 15. positioning pins; 16. a workpiece side surface lower pressing plate; 17. pressing plates are arranged on the side surfaces of the workpieces; 18. punching the nail downwards; 19. punching a nail upwards; 20. a hexagon socket head cap screw; 21. a lower die spring guide rod; 22. a nail punching return spring; 23. a flat washer; 24. locking the nut; 25. a mold core; 2501. a prism structure; 2502. a square base; 2503. upper and lower step surfaces; 2504. a lower punch hole; 2505. a guiding and positioning surface; 2506. a second wing plate; 2507. punching a hole die; 2508. scrap hole; 26. a spring thimble; 27. a base; 28. a lower die holder; 2801. a rectangular groove; 2802. a blanking hole; 2803. a spring stop; 29. a slider return spring; 30. a guide bar slide rail; 31. a guide rod slider; 32. u curved link plate work piece.

The specific implementation mode is as follows:

the invention provides a horizontal floating punching device for a U-shaped bent chain plate.

The punching method of the horizontal floating punching device comprises the following specific steps:

b. The punch press slide block continues to move downwards, the driving piece 7 pushes the driving slide block 13 to move towards the middle along with the guide rod slide block 31 along the guide rod slide rail 30, the hook plates 6 on the two sides of the driving piece 7 slide into the return groove 1304 of the driving slide block 13, the slide block return spring 29 and the punching nail return spring 22 are compressed, at the moment, the workpiece pressing plate 3 presses the U-shaped bent chain plate workpiece 32 to the punching position of the mold core 25, and meanwhile, the workpiece side surface lower pressing plate 16 and the workpiece side surface upper pressing plate 17 respectively press the left side surface and the right side surface of the U-shaped bent chain plate workpiece 32. Wherein, the hook plate 6 is a common hook plate; the punch pin return spring 22 and the slide block return spring 29 are common springs; the guide bar slide rail 30 is a low-speed heavy-load guide bar slide rail; the return slot 1304 on the drive slider 13 is a slanted groove.

Claims

1. A horizontal floating punching device for a U-shaped bent chain plate is characterized by comprising an upper die mechanism, a guide mechanism, a punching nail driving mechanism, a die core mechanism and a die holder mechanism; the upper die mechanism comprises a die handle (1), an upper die base (2), a workpiece pressing plate (3), an upper die spring guide rod (4), a material pressing spring (5), a hook plate (6), a driving piece (7) and a driving piece fixing plate (8); a flange is arranged at the bottom of the die handle (1), a flange hole is arranged in the middle of the upper die holder (2), and the flange is in clearance fit with the flange hole and is fixedly connected with the flange hole through a bolt; the lower end of the driving piece (7) is provided with a 45-degree inclined plane, the upper end of the driving piece (7) is provided with a tenon, and the tenon of the driving piece (7) is positioned in a mortise of the driving piece fixing plate (8); the driving pieces (7) are arranged symmetrically left and right, and the driving pieces (7) are fixedly connected to the driving piece fixing plate (8) through bolts; the driving piece fixing plate (8) is fixedly connected with the upper die holder (2) through a screw; the detachable hook plate (6) is arranged in the L-shaped slotted holes on the front side surface and the rear side surface of the driving piece (7), the hook plate (6) is Z-shaped, and two sides of the hook plate (6) are respectively provided with a protruding cylindrical pin shaft; the workpiece pressing plate (3) is a rectangular plate with two through holes on two sides, the upper die spring guide rod (4) comprises two parts, the workpiece pressing plate (3) and the pressing spring (5) are sequentially sleeved on the upper die spring guide rod (4) in an empty mode, and the upper die spring guide rod (4) is fixedly connected with a screw hole in the middle of the driving piece fixing plate (8) through a threaded end of the upper die spring guide rod; the guide mechanisms comprise guide sleeves (9), guide columns (10), springs (11) and guide column bases (12), and the two guide mechanisms are symmetrically distributed behind the punching device in the left-right direction; the guide sleeve (9) is fixed at the lower parts of the left side and the right side of the upper die holder (2) through bolts, the guide pillar (10) is fixed at the left side and the right side of a base (27) in the die holder mechanism through the guide pillar base (12), the spring (11) and the guide sleeve (9) are sequentially sleeved on the guide pillar (10) in a hollow mode, and the guide sleeve (9) is in clearance fit with the guide pillar (10); the punching nail driving mechanism comprises a driving slide block (13), a punching nail fixing plate (14), a workpiece side surface lower pressing plate (16), a workpiece side surface upper pressing plate (17), a lower punching nail (18), an upper punching nail (19), a lower die spring guide rod (21) and a punching nail return spring (22); the nail punching driving mechanisms are of front-back symmetrical structures, and the nail punching driving mechanisms are divided into two parts and are symmetrically arranged on the left side and the right side of the die core mechanism; the middle of the driving sliding block (13) is provided with a 45-degree inclined plane body (1301), two side faces of the inclined plane body (1301) are provided with return grooves (1304) matched with the hook plates (6) for use, two sides of the inclined plane body (1301) are respectively provided with two through holes (1302) with the same structure, the through holes (1302) are used for placing the lower die spring guide rod (21) and the punching pin return spring (22), the bottom face of the driving sliding block (13) is provided with a spring stop dog (1305), the front side and the rear side of the driving sliding block (13) are respectively provided with a first wing plate (1303), and the first wing plate (1303) is respectively provided with 8 uniformly distributed mounting holes; the first wing plates (1303) are fixedly connected with guide rod sliding blocks (31) in the die holder mechanism respectively, and the driving sliding blocks (13) can horizontally move left and right along guide rod sliding rails (30) in the die holder mechanism; the punching pin fixing plate (14) is fixedly connected with the driving slide block (13); the lower punching nails (18) and the upper punching nails (19) are fixedly connected in upper and lower counter bores of the punching nail fixing plate (14) respectively; the lower die spring guide rods (21) are four in number, the lower die spring guide rods (21) sequentially penetrate through the workpiece side lower pressing plate (16) or the workpiece side upper pressing plate (17), the punching nail return spring (22), the punching nail fixing plate (14) and the driving slide block (13), and the lower die spring guide rods (21) are locked through flat washers (23) and locking nuts (24); a through hole for the lower punch pin (18) to pass through is formed in the middle of the workpiece side lower pressing plate (16), and counter bores matched with the lower die spring guide rod (21) are symmetrically formed in two sides of the workpiece side lower pressing plate (16); a protruding step surface which is the same as the upper step surface and the lower step surface (2503) in the die core mechanism in shape is arranged in the middle of the workpiece side upper pressure plate (17), a through hole for the upper punching nail (19) to pass through is formed in the upper end of the protruding step surface, and counter bores which are matched with the lower die spring guide rod (21) are symmetrically formed in two sides of the workpiece side upper pressure plate (17); the mold core mechanism comprises a mold core (25) and a spring thimble (26); the mold core (25) is of a left-right front-back symmetrical structure, the middle part of the mold core (25) is of a prism structure (2501) with a square base (2502), and the front side and the back side of the prism structure (2501) are respectively provided with a second wing plate (2506); the middle of the prism structure (2501) is a square scrap hole (2508), and the left end surface and the right end surface of the prism structure (2501) are respectively provided with an upper step surface and a lower step surface (2503); two sides of the upper step surface (2503) and the lower step surface (2503) are provided with guide positioning surfaces (2505) of U-shaped bent chain plate workpieces (32); an upper punch hole (2507) and a lower punch hole (2504) are respectively formed in the upper step surface and the lower step surface (2503), wherein the upper punch hole (2507) is a three-fifths circular arc-shaped through hole; the positions and the center distance of the upper punch hole (2507) and the lower punch hole (2504) are consistent with the positions and the center distance of two holes of the processed U-shaped bent chain plate workpiece (32); the upper punch hole (2507) and the lower punch hole (2504) respectively form a punch-die of the horizontal floating punching device together with the upper punch pin (19) and the lower punch pin (18); a blind hole for mounting the spring thimble (26) is formed in each square base (2502) on the outer side of the lower punch hole (2504); the second wing plates (2506) on the front side and the rear side of the mold core (25) are respectively provided with four mounting holes, the second wing plates (2506) on the front side and the rear side of the mold core (25) are fixedly connected with guide rod sliding blocks (31) in the mold base mechanism through bolts, and the mold core (25) can horizontally float left and right along the guide rod sliding rails (30) in the mold base mechanism, so that horizontal floating punching is realized; the die holder mechanism comprises a base (27), a lower die holder (28), a slider return spring (29), a guide rod slide rail (30) and a guide rod slider (31); the base (27) is fixedly installed on a working table of a punch press, the lower die holder (28) is fixedly connected to the base (27), a square blanking hole (2802) is formed in the middle of the lower die holder (28), the square blanking holes with the same size are also formed in the middles of the base (27) and the working table of the punch press, four rectangular grooves (2801) for accommodating the slider return springs (29) and spring stoppers (2803) are formed in the lower die holder (28), and the spring stoppers (2803) can limit the range of left and right horizontal floating of the die cores (25) along the guide rod slide rails (30); the front side and the rear side of the lower die seat (28) are respectively fixed with the guide rod slide rails (30), and each guide rod slide rail (30) is respectively provided with five guide rod slide blocks (31) with the same structure; the guide rod slide rail (30) and the guide rod slide block (31) are both heavy-duty.

2. The punching method of a horizontal floating punching device for a U-bend link plate according to claim 1, characterized in that the punching method comprises the following specific steps:

a. firstly, a manipulator clamping jaw places the U-shaped bent chain plate workpiece (32) on the mold core (25), the workpiece pressing plate (3) contacts the U-shaped bent chain plate workpiece (32) along the descending motion of a punch press slide block, the U-shaped bent chain plate workpiece (32) is forced to move downwards along the guide positioning surface (2505), the U-shaped bent chain plate workpiece (32) contacts and presses down the spring ejector pin (26), and then the inclined surface of the driving piece (7) contacts the inclined surface body (1301) of the driving slide block (13);

b. the punch press sliding block continues to move downwards, the driving piece (7) pushes the driving sliding block (13) to move towards the middle along with the guide rod sliding block (31) along the guide rod sliding rail (30) in the horizontal direction, the hook plates (6) on the two sides of the driving piece (7) slide into the return groove (1304) of the driving sliding block (13), the sliding block return spring (29) and the punching nail return spring (22) are compressed, at the moment, the workpiece pressing plate (3) presses the U-shaped bent chain plate workpiece (32) to the punching position of the mold core (25), and meanwhile, the workpiece side surface lower pressing plate (16) and the workpiece side surface upper pressing plate (17) respectively press the left side surface and the right side surface of the U-shaped bent chain plate workpiece (32);

c. the lower punching nails (18) and the upper punching nails (19) on the two sides of the mold core (25) are pushed by the driving piece (7) to start to contact the U-shaped bent chain plate workpiece (32), if the lower punching nails (18) and the upper punching nails (19) on the two sides of the mold core (25) are not in synchronous contact with the U-shaped bent chain plate workpiece (32), the punching nails which are firstly in contact with the U-shaped bent chain plate workpiece (32) push the mold core (25) to horizontally float to the punching nails on the two sides along the guide rod slide rail (30) and synchronously contact the U-shaped bent chain plate workpiece (32), then the lower punching nails (18) and the upper punching nails (19) on the two sides of the mold core (25) synchronously complete the punching of the four holes of the U-shaped bent chain plate workpiece (32) under the pushing of the driving piece (7), punching scraps fall into the scrap holes (2508) in the middle of the mold core (25), and the square blanking holes (2) and the blanking holes (2802) of the lower mold base (28) sequentially pass through, The square blanking holes of the base (27) and the square blanking holes of the working table of the punch press are discharged;

d. at the moment, the punch press slide block reaches the bottom dead center position of the punch press, and the stroke is finished;

e. the punch press sliding block returns, the driving piece (7) is gradually separated from the driving sliding block (13), and the driving sliding block (13) horizontally moves outwards under the action of the elastic force of the sliding block return spring (29);

f. meanwhile, the punching pin return spring (22) drives the lower punching pin (18) and the upper punching pin (19) to retreat and reset;

g. if the reset is blocked, the hook plates (6) on the two sides of the driving piece (7) are inserted into the return groove (1304) to forcibly withdraw the driving slide block (13) so as to protect the mold core (25);

h. the spring ejector pin (26) pushes the U-shaped bent chain plate workpiece (32) on the mold core (25) loose under the action of spring force, and then a clamping jaw of the manipulator takes out the U-shaped bent chain plate workpiece (32);